17 inch quad, cube black, weird yaw and throttle behavior

My critical fail-safe is still untouched. It was the low battery failsafe/warning that I lowered. It’s set to do nothing so all it dose is to send the telemetry warning.

So if I set it to measure correctly at lower voltages, and I use the voltage meter to know when to land. Won’t that be dangerous if it reads wrong at my 6s battery voltage??

If you have a bench power supply you can use that set to 20.0 volts (or similar) to calibrate the power module (voltage multiplier) so that the reading is most accurate around the critical battery voltages.
It doesnt matter if the reading is a little wrong while the battery pack is fully charged.

ok, My sky rc battery charger had a 12v power supply, that’s the closest I can get with a power supply. I got the value quite close. But moving around the wire and unplugging than plugging in the battery again can cause it to measure another voltage. Even if the battery is at the same voltage and the multiplier the same. (I measure the battery voltage while it’s connected to the module to set an accurate value)

Edit: The module seems to work fine as of now

I tried auto-tune today, with no success. It flew better on the settings before the auto-tune than after. It’s quite stable, although when I fly forward or sideways a bit faster, I can hear a steady oscillation occurring.

Also, when doing some maneuvers, I can hear a sort of crackling sound. Like crck crack crack, with a frequency. So not a constant sound but more like something is moving on the copter. I increased the dmag compensation but it didn’t help.

It also clipps like all hell on the third IMU. I flew hard but it should be able to handle that just fine.

Log: https://drive.google.com/file/d/1umCe1_C6KK555btN0nx9z06O0vIrFY8k/view?usp=sharing

The log might be quite useless since I didn’t carry out the maneuvers systematically.
I could do another flight tomorrow and test for different things if needed.


IMO you have 2 options.
A) Reset the parameters back to the attached and fly it as is and forget about Auto Tune (perhaps some minor manual live tuning)
Flying good.bin.param (17.0 KB)
B) get a handle on those very high vibrations with some mechanical re-work and then try Auto Tune again. I would not suggest running it at the .07 aggression you set but just my opinion. Too many times have we seen a bad Auto Tune with aggression too low.


I ran it on 0.1 before that. But with no good result either. I changed to 0.7 just to see if a difference would change the outcome. It didn’t.

I will probably go back to the previous settings, but the vibrations will brig down performance.
I saved a picture of my extended tuning page. Can’t I just sett all settings back to what they were before auto-tune? Or does auto-tune affect other settings as well?

Edit: How do you get my parameters from the log?

I would use parameter compare and reset them manually.

With the Create KML+gpx button in Mission Planner.


I think maybe my soft mounted motors could be causing more problems than I taught (the crackling noise). They are aluminum and the only other once I have are the standard tarot plastic mounts. Should I still switch to the hard-mounted once? To maybe help the vibration issue?

Didn’t we already talk about that? I think for sure you would want to do that. You want high rigidity everywhere except some isolation for the FC. Whether it’s internal or external isolation depending on the FC. My best performing craft have super rigid frames and super gumby FC mounts*. The only FC I have with IMU isolation is an older Kakute F7 AIO and it’s done poorly on that board.
*Some will say that you can have a too compliant FC mount but so far that has not been my experience. There are mounts supported by 4 O-rings and those have worked well for some.

Yeah, we talked about it.

I tried to convert the aluminum mounts to hard-mounts but was not successful.
I’m afraid that the plastic tarot mounts will break or twist on the arm since I’ve heard so much bad about them.

But I could try them tomorrow and test fly them for a vibration check

I haven’t got a hold of new mounts for the motors. The only once I have are the plastic once and I don’t trust them at all. Have had one crack and bend on me in flight. I’ll try to get some aluminum once to try out.

I also got a hold of some 18 inch foldable propellers. The drone takes up so much space right now so I wanted to try out some foldable. The 17 inch I have does not come in a foldable version, only 16 and 18 does.

So, first of: Do I only need to change the mission-planner helper and do some fine tuning or do I need to change more?

Second, i use t-motor mn4014 330kv motors. T-motor only tested them for 15 to 17 inch. Based on the motor kv and voltage (6s lipo), do you think I can test 18 inch?


There will be changes as a result of greater thrust lower motor RPM but starting with the Initial Parameters Setup is the 1st step. It will effect the Rate PID values and motor hover thrust.
What is the take-off weight of this craft with that battery?

The takeoff weight is 2.5kg (5.5 lb). I a bit worried that such low rpm at hover (about 3000) would be to little to give the drone room to compensate with motor thrust.

Tarot makes 17" folding props.

yeah, I’ve seen those. The thing is that I have a set of 18 inch once and I don’t want to spend money if I don’t have too. I have a more important project coming up that needs the money.

If I test with 18 inch propellers, and the motor wont get hot after 30 min of hover. Do you think that I could use them?

!!off course I won’t blame you if I mess up by switching props and break something!!
(I would not be surprised if you’ve gotten blamed before regarding how much you help here)

Yes, I think so. A quick run thru eCalc doesn’t raise any red flags. Review this again:

Setting Motor range

Thanks! I’ll set up the vehicle to use 18 inch propellers and try to conduct a test-flight during the weekend.

By the way, this topic has evolved into much more than just sorting out a yaw and throttle issue.

It’s more about setup and experiments on my craft now. Should I create a new topic akd link it here so that this one stays more relater to the yaw issue?


Yes, if you think a new topic is needed. I agree this titled one was tapped out a long time ago.

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The new topic:

We can continue the discussion here!